Make dwarf_expr_piece::pieces an std::vector

Change the manually managed array dwarf_expr_piece::piece with an
std::vector.  After passing the pieces array to allocate_piece_closure,
dwarf2_evaluate_loc_desc_full doesn't need that data anymore.  We can
therefore move the content of the vector to avoid copying it.

Reg-tested on the buildbot.

gdb/ChangeLog:

	* dwarf2expr.h (struct dwarf_expr_piece): Move up.
	(struct dwarf_expr_context) <n_pieces>: Remove.
	<pieces>: Change type to std::vector.
	* dwarf2expr.c (dwarf_expr_context::dwarf_expr_context): Adjust.
	(dwarf_expr_context::~dwarf_expr_context): Don't manually free
	pieces.
	(dwarf_expr_context::add_piece): Adjust.
	* dwarf2loc.c (struct piece_closure): Initialize fields.
	<n_pieces>: Remove.
	<pieces>: Change type to std::vector.
	(allocate_piece_closure): Adjust, change parameter to
	std::vector rvalue and std::move it to piece_closure.
	(rw_pieced_value): Adjust.
	(check_pieced_synthetic_pointer): Adjust.
	(indirect_synthetic_pointer): Adjust.
	(coerce_pieced_ref): Adjust.
	(free_pieced_value_closure):  Adjust.  Use delete to free
	piece_closure.
	(dwarf2_evaluate_loc_desc_full): Adjust.  std::move ctx.pieces
	to allocate_piece_closure.
	(dwarf2_loc_desc_get_symbol_read_needs): Adjust.
This commit is contained in:
Simon Marchi 2017-09-14 15:57:01 +02:00
parent 4d465c689a
commit 1e46716193
4 changed files with 124 additions and 124 deletions

View file

@ -1,3 +1,27 @@
2017-09-14 Simon Marchi <simon.marchi@ericsson.com>
* dwarf2expr.h (struct dwarf_expr_piece): Move up.
(struct dwarf_expr_context) <n_pieces>: Remove.
<pieces>: Change type to std::vector.
* dwarf2expr.c (dwarf_expr_context::dwarf_expr_context): Adjust.
(dwarf_expr_context::~dwarf_expr_context): Don't manually free
pieces.
(dwarf_expr_context::add_piece): Adjust.
* dwarf2loc.c (struct piece_closure): Initialize fields.
<n_pieces>: Remove.
<pieces>: Change type to std::vector.
(allocate_piece_closure): Adjust, change parameter to
std::vector rvalue and std::move it to piece_closure.
(rw_pieced_value): Adjust.
(check_pieced_synthetic_pointer): Adjust.
(indirect_synthetic_pointer): Adjust.
(coerce_pieced_ref): Adjust.
(free_pieced_value_closure): Adjust. Use delete to free
piece_closure.
(dwarf2_evaluate_loc_desc_full): Adjust. std::move ctx.pieces
to allocate_piece_closure.
(dwarf2_loc_desc_get_symbol_read_needs): Adjust.
2017-09-12 Simon Marchi <simon.marchi@ericsson.com> 2017-09-12 Simon Marchi <simon.marchi@ericsson.com>
* probe.h (probe_ops_cp): Remove typedef. * probe.h (probe_ops_cp): Remove typedef.

View file

@ -100,9 +100,7 @@ dwarf_expr_context::dwarf_expr_context ()
location (DWARF_VALUE_MEMORY), location (DWARF_VALUE_MEMORY),
len (0), len (0),
data (NULL), data (NULL),
initialized (0), initialized (0)
num_pieces (0),
pieces (NULL)
{ {
this->stack = XNEWVEC (struct dwarf_stack_value, this->stack_allocated); this->stack = XNEWVEC (struct dwarf_stack_value, this->stack_allocated);
} }
@ -112,7 +110,6 @@ dwarf_expr_context::dwarf_expr_context ()
dwarf_expr_context::~dwarf_expr_context () dwarf_expr_context::~dwarf_expr_context ()
{ {
xfree (this->stack); xfree (this->stack);
xfree (this->pieces);
} }
/* Expand the memory allocated stack to contain at least /* Expand the memory allocated stack to contain at least
@ -285,47 +282,42 @@ dwarf_expr_context::stack_empty_p () const
void void
dwarf_expr_context::add_piece (ULONGEST size, ULONGEST offset) dwarf_expr_context::add_piece (ULONGEST size, ULONGEST offset)
{ {
struct dwarf_expr_piece *p; this->pieces.emplace_back ();
dwarf_expr_piece &p = this->pieces.back ();
this->num_pieces++; p.location = this->location;
p.size = size;
p.offset = offset;
this->pieces if (p.location == DWARF_VALUE_LITERAL)
= XRESIZEVEC (struct dwarf_expr_piece, this->pieces, this->num_pieces);
p = &this->pieces[this->num_pieces - 1];
p->location = this->location;
p->size = size;
p->offset = offset;
if (p->location == DWARF_VALUE_LITERAL)
{ {
p->v.literal.data = this->data; p.v.literal.data = this->data;
p->v.literal.length = this->len; p.v.literal.length = this->len;
} }
else if (stack_empty_p ()) else if (stack_empty_p ())
{ {
p->location = DWARF_VALUE_OPTIMIZED_OUT; p.location = DWARF_VALUE_OPTIMIZED_OUT;
/* Also reset the context's location, for our callers. This is /* Also reset the context's location, for our callers. This is
a somewhat strange approach, but this lets us avoid setting a somewhat strange approach, but this lets us avoid setting
the location to DWARF_VALUE_MEMORY in all the individual the location to DWARF_VALUE_MEMORY in all the individual
cases in the evaluator. */ cases in the evaluator. */
this->location = DWARF_VALUE_OPTIMIZED_OUT; this->location = DWARF_VALUE_OPTIMIZED_OUT;
} }
else if (p->location == DWARF_VALUE_MEMORY) else if (p.location == DWARF_VALUE_MEMORY)
{ {
p->v.mem.addr = fetch_address (0); p.v.mem.addr = fetch_address (0);
p->v.mem.in_stack_memory = fetch_in_stack_memory (0); p.v.mem.in_stack_memory = fetch_in_stack_memory (0);
} }
else if (p->location == DWARF_VALUE_IMPLICIT_POINTER) else if (p.location == DWARF_VALUE_IMPLICIT_POINTER)
{ {
p->v.ptr.die_sect_off = (sect_offset) this->len; p.v.ptr.die_sect_off = (sect_offset) this->len;
p->v.ptr.offset = value_as_long (fetch (0)); p.v.ptr.offset = value_as_long (fetch (0));
} }
else if (p->location == DWARF_VALUE_REGISTER) else if (p.location == DWARF_VALUE_REGISTER)
p->v.regno = value_as_long (fetch (0)); p.v.regno = value_as_long (fetch (0));
else else
{ {
p->v.value = fetch (0); p.v.value = fetch (0);
} }
} }

View file

@ -49,6 +49,53 @@ enum dwarf_value_location
DWARF_VALUE_IMPLICIT_POINTER DWARF_VALUE_IMPLICIT_POINTER
}; };
/* A piece of an object, as recorded by DW_OP_piece or DW_OP_bit_piece. */
struct dwarf_expr_piece
{
enum dwarf_value_location location;
union
{
struct
{
/* This piece's address, for DWARF_VALUE_MEMORY pieces. */
CORE_ADDR addr;
/* Non-zero if the piece is known to be in memory and on
the program's stack. */
int in_stack_memory;
} mem;
/* The piece's register number, for DWARF_VALUE_REGISTER pieces. */
int regno;
/* The piece's literal value, for DWARF_VALUE_STACK pieces. */
struct value *value;
struct
{
/* A pointer to the data making up this piece,
for DWARF_VALUE_LITERAL pieces. */
const gdb_byte *data;
/* The length of the available data. */
ULONGEST length;
} literal;
/* Used for DWARF_VALUE_IMPLICIT_POINTER. */
struct
{
/* The referent DIE from DW_OP_implicit_pointer. */
sect_offset die_sect_off;
/* The byte offset into the resulting data. */
LONGEST offset;
} ptr;
} v;
/* The length of the piece, in bits. */
ULONGEST size;
/* The piece offset, in bits. */
ULONGEST offset;
};
/* The dwarf expression stack. */ /* The dwarf expression stack. */
struct dwarf_stack_value struct dwarf_stack_value
@ -114,8 +161,7 @@ struct dwarf_expr_context
initialized; zero otherwise. */ initialized; zero otherwise. */
int initialized; int initialized;
/* An array of pieces. PIECES points to its first element; /* A vector of pieces.
NUM_PIECES is its length.
Each time DW_OP_piece is executed, we add a new element to the Each time DW_OP_piece is executed, we add a new element to the
end of this array, recording the current top of the stack, the end of this array, recording the current top of the stack, the
@ -137,8 +183,7 @@ struct dwarf_expr_context
no DW_OP_piece operations have no value to place in a piece's no DW_OP_piece operations have no value to place in a piece's
'size' field; the size comes from the surrounding data. So the 'size' field; the size comes from the surrounding data. So the
two cases need to be handled separately.) */ two cases need to be handled separately.) */
int num_pieces; std::vector<dwarf_expr_piece> pieces;
struct dwarf_expr_piece *pieces;
/* Return the value of register number REGNUM (a DWARF register number), /* Return the value of register number REGNUM (a DWARF register number),
read as an address. */ read as an address. */
@ -213,54 +258,6 @@ private:
void pop (); void pop ();
}; };
/* A piece of an object, as recorded by DW_OP_piece or DW_OP_bit_piece. */
struct dwarf_expr_piece
{
enum dwarf_value_location location;
union
{
struct
{
/* This piece's address, for DWARF_VALUE_MEMORY pieces. */
CORE_ADDR addr;
/* Non-zero if the piece is known to be in memory and on
the program's stack. */
int in_stack_memory;
} mem;
/* The piece's register number, for DWARF_VALUE_REGISTER pieces. */
int regno;
/* The piece's literal value, for DWARF_VALUE_STACK pieces. */
struct value *value;
struct
{
/* A pointer to the data making up this piece,
for DWARF_VALUE_LITERAL pieces. */
const gdb_byte *data;
/* The length of the available data. */
ULONGEST length;
} literal;
/* Used for DWARF_VALUE_IMPLICIT_POINTER. */
struct
{
/* The referent DIE from DW_OP_implicit_pointer. */
sect_offset die_sect_off;
/* The byte offset into the resulting data. */
LONGEST offset;
} ptr;
} v;
/* The length of the piece, in bits. */
ULONGEST size;
/* The piece offset, in bits. */
ULONGEST offset;
};
void dwarf_expr_require_composition (const gdb_byte *, const gdb_byte *, void dwarf_expr_require_composition (const gdb_byte *, const gdb_byte *,
const char *); const char *);

View file

@ -1479,16 +1479,13 @@ value_of_dwarf_block_entry (struct type *type, struct frame_info *frame,
struct piece_closure struct piece_closure
{ {
/* Reference count. */ /* Reference count. */
int refc; int refc = 0;
/* The CU from which this closure's expression came. */ /* The CU from which this closure's expression came. */
struct dwarf2_per_cu_data *per_cu; struct dwarf2_per_cu_data *per_cu = NULL;
/* The number of pieces used to describe this variable. */ /* The pieces describing this variable. */
int n_pieces; std::vector<dwarf_expr_piece> pieces;
/* The pieces themselves. */
struct dwarf_expr_piece *pieces;
/* Frame ID of frame to which a register value is relative, used /* Frame ID of frame to which a register value is relative, used
only by DWARF_VALUE_REGISTER. */ only by DWARF_VALUE_REGISTER. */
@ -1500,25 +1497,23 @@ struct piece_closure
static struct piece_closure * static struct piece_closure *
allocate_piece_closure (struct dwarf2_per_cu_data *per_cu, allocate_piece_closure (struct dwarf2_per_cu_data *per_cu,
int n_pieces, struct dwarf_expr_piece *pieces, std::vector<dwarf_expr_piece> &&pieces,
struct frame_info *frame) struct frame_info *frame)
{ {
struct piece_closure *c = XCNEW (struct piece_closure); struct piece_closure *c = new piece_closure;
int i; int i;
c->refc = 1; c->refc = 1;
c->per_cu = per_cu; c->per_cu = per_cu;
c->n_pieces = n_pieces; c->pieces = std::move (pieces);
c->pieces = XCNEWVEC (struct dwarf_expr_piece, n_pieces);
if (frame == NULL) if (frame == NULL)
c->frame_id = null_frame_id; c->frame_id = null_frame_id;
else else
c->frame_id = get_frame_id (frame); c->frame_id = get_frame_id (frame);
memcpy (c->pieces, pieces, n_pieces * sizeof (struct dwarf_expr_piece)); for (dwarf_expr_piece &piece : c->pieces)
for (i = 0; i < n_pieces; ++i) if (piece.location == DWARF_VALUE_STACK)
if (c->pieces[i].location == DWARF_VALUE_STACK) value_incref (piece.v.value);
value_incref (c->pieces[i].v.value);
return c; return c;
} }
@ -1816,10 +1811,10 @@ rw_pieced_value (struct value *v, struct value *from)
max_offset = 8 * TYPE_LENGTH (value_type (v)); max_offset = 8 * TYPE_LENGTH (value_type (v));
/* Advance to the first non-skipped piece. */ /* Advance to the first non-skipped piece. */
for (i = 0; i < c->n_pieces && bits_to_skip >= c->pieces[i].size; i++) for (i = 0; i < c->pieces.size () && bits_to_skip >= c->pieces[i].size; i++)
bits_to_skip -= c->pieces[i].size; bits_to_skip -= c->pieces[i].size;
for (; i < c->n_pieces && offset < max_offset; i++) for (; i < c->pieces.size () && offset < max_offset; i++)
{ {
struct dwarf_expr_piece *p = &c->pieces[i]; struct dwarf_expr_piece *p = &c->pieces[i];
size_t this_size_bits, this_size; size_t this_size_bits, this_size;
@ -2079,7 +2074,7 @@ check_pieced_synthetic_pointer (const struct value *value, LONGEST bit_offset,
if (value_bitsize (value)) if (value_bitsize (value))
bit_offset += value_bitpos (value); bit_offset += value_bitpos (value);
for (i = 0; i < c->n_pieces && bit_length > 0; i++) for (i = 0; i < c->pieces.size () && bit_length > 0; i++)
{ {
struct dwarf_expr_piece *p = &c->pieces[i]; struct dwarf_expr_piece *p = &c->pieces[i];
size_t this_size_bits = p->size; size_t this_size_bits = p->size;
@ -2200,7 +2195,7 @@ indirect_pieced_value (struct value *value)
if (value_bitsize (value)) if (value_bitsize (value))
bit_offset += value_bitpos (value); bit_offset += value_bitpos (value);
for (i = 0; i < c->n_pieces && bit_length > 0; i++) for (i = 0; i < c->pieces.size () && bit_length > 0; i++)
{ {
struct dwarf_expr_piece *p = &c->pieces[i]; struct dwarf_expr_piece *p = &c->pieces[i];
size_t this_size_bits = p->size; size_t this_size_bits = p->size;
@ -2271,10 +2266,11 @@ coerce_pieced_ref (const struct value *value)
/* gdb represents synthetic pointers as pieced values with a single /* gdb represents synthetic pointers as pieced values with a single
piece. */ piece. */
gdb_assert (closure != NULL); gdb_assert (closure != NULL);
gdb_assert (closure->n_pieces == 1); gdb_assert (closure->pieces.size () == 1);
return indirect_synthetic_pointer (closure->pieces->v.ptr.die_sect_off, return indirect_synthetic_pointer
closure->pieces->v.ptr.offset, (closure->pieces[0].v.ptr.die_sect_off,
closure->pieces[0].v.ptr.offset,
closure->per_cu, frame, type); closure->per_cu, frame, type);
} }
else else
@ -2303,14 +2299,11 @@ free_pieced_value_closure (struct value *v)
--c->refc; --c->refc;
if (c->refc == 0) if (c->refc == 0)
{ {
int i; for (dwarf_expr_piece &p : c->pieces)
if (p.location == DWARF_VALUE_STACK)
value_free (p.v.value);
for (i = 0; i < c->n_pieces; ++i) delete c;
if (c->pieces[i].location == DWARF_VALUE_STACK)
value_free (c->pieces[i].v.value);
xfree (c->pieces);
xfree (c);
} }
} }
@ -2390,21 +2383,20 @@ dwarf2_evaluate_loc_desc_full (struct type *type, struct frame_info *frame,
} }
END_CATCH END_CATCH
if (ctx.num_pieces > 0) if (ctx.pieces.size () > 0)
{ {
struct piece_closure *c; struct piece_closure *c;
ULONGEST bit_size = 0; ULONGEST bit_size = 0;
int i; int i;
for (i = 0; i < ctx.num_pieces; ++i) for (dwarf_expr_piece &piece : ctx.pieces)
bit_size += ctx.pieces[i].size; bit_size += piece.size;
/* Complain if the expression is larger than the size of the /* Complain if the expression is larger than the size of the
outer type. */ outer type. */
if (bit_size > 8 * TYPE_LENGTH (type)) if (bit_size > 8 * TYPE_LENGTH (type))
invalid_synthetic_pointer (); invalid_synthetic_pointer ();
c = allocate_piece_closure (per_cu, ctx.num_pieces, ctx.pieces, c = allocate_piece_closure (per_cu, std::move (ctx.pieces), frame);
frame);
/* We must clean up the value chain after creating the piece /* We must clean up the value chain after creating the piece
closure but before allocating the result. */ closure but before allocating the result. */
free_values.free_to_mark (); free_values.free_to_mark ();
@ -2866,16 +2858,11 @@ dwarf2_loc_desc_get_symbol_read_needs (const gdb_byte *data, size_t size,
in_reg = ctx.location == DWARF_VALUE_REGISTER; in_reg = ctx.location == DWARF_VALUE_REGISTER;
if (ctx.num_pieces > 0)
{
int i;
/* If the location has several pieces, and any of them are in /* If the location has several pieces, and any of them are in
registers, then we will need a frame to fetch them from. */ registers, then we will need a frame to fetch them from. */
for (i = 0; i < ctx.num_pieces; i++) for (dwarf_expr_piece &p : ctx.pieces)
if (ctx.pieces[i].location == DWARF_VALUE_REGISTER) if (p.location == DWARF_VALUE_REGISTER)
in_reg = 1; in_reg = 1;
}
if (in_reg) if (in_reg)
ctx.needs = SYMBOL_NEEDS_FRAME; ctx.needs = SYMBOL_NEEDS_FRAME;